Manifold fitting for a compressed air tank

ABSTRACT

A manifold fitting for a compressed air tank comprising an elongate main body of hexagonal cross-section having an axial passage for communication with the tank, a first lateral opening extending from a first face of the body, an outlet member threaded in the first lateral opening having a valve seat at its inner end and a second lateral opening extending from a second face opposite the first. A valve member is threaded in the second lateral opening extending across the stem with an axial passage therein extending inwardly partway from its outer end to at least one port in the valve stem for communication with the axial passage. A filler check valve is located in the axial passage for filling the tank with compressed air via application of a coupling at the end of a compressed air supply to said stem. A third lateral opening extends inwardly from a third face to said passage and has a pressure relief safety valve therein. A fourth threaded lateral opening in the body extends inwardly from a fourth of the faces to the passage for receiving a pressure gauge.

BACKGROUND OF THE INVENTION

This invention relates to a manifold fitting, and more particularly to amanifold fitting for a compressed air tank.

The invention is in the same general field as the manifold assemblyshown in U.S. Pat. No. 4,120,319 issued Oct. 17, 1978 and co-pendingU.S. patent application Ser. No. 723,135, filed on Apr. 15, 1985, andinvolves improvements thereover.

SUMMARY OF THE INVENTION

Among the several objects of this invention may be noted the provisionof a manifold fitting for a compressed air tank with components whichcan be easily interchanged; the provision of such a manifold fittingthat has the flexibility of changing to various configurations; and theprovision of such a manifold fitting which is simple in construction,inexpensive to manufacture, easy to install and reliable in operation.

In general, a manifold fitting of this invention is designed for acompressed air tank and comprises an elongate main body of hexagonalcross-section with first and second ends, the first end being of reducedcircular cross-section. The main body has an axial passage extendingfrom the first end toward and terminating short of the second end. Thefirst end of the main body is externally threaded for attachment of thefitting to a tank for communication with the tank via the passage. Thebody also has a first lateral opening extending inwardly to the axialpassage from a first face of six faces of the body. An outlet member isthreaded in the first lateral opening in the body and has a valve seatat its inner end toward the passage. A second lateral opening in thebody extends inwardly to the axial passage from a second of the sixfaces of the body opposite the first face. The second lateral opening isopposite the first lateral opening and is in axial alignment therewith.A valve member is threaded in the second lateral opening and extendsacross the passage with space around it for flow of air through thepassage. The valve member is adapted to be threaded inwardly in thesecond lateral opening to a closed position in engagement with the valveseat and to be threaded outwardly with respect to the second lateralopening to an open position for flow of air from the tank through thepassage and out through the outlet member. The valve member further hasa stem with an axial passage therein which extends inwardly partway fromits outer end to at least one port in the valve stem for communicationwith the axial passage in the main body. A filler check valve issituated within the axial passage in the stem for filling the tank withcompressed air via application of a coupling at the end of a compressedair supply to the stem. A pressure relief safety valve is provided at athird lateral opening extending inwardly from a third of the six facesof the main body. The main body further has a fourth threaded lateralopening for a pressure gauge.

This invention is also directed to the process of providing a metalmanifold with a pressure safety valve. In the process, the manifold hasa face, an internal fluid passage, a lateral opening extending from theface inwardly to the internal fluid passage, a cross-passageintersecting the lateral opening, and a valve seat between the fluidpassage and the intersection of the lateral opening and thecross-passage. The opening has a first diameter near the internal fluidpassage and an enlarged diameter near the face providing a shoulder. Themethod comprises several steps. First, a valve member is inserted in thelateral opening. The valve member is movable toward and away from thevalve seat. Next, a spring means is inserted for biasing the valvemember against the valve seat. Then, a closure is inserted in theopening above and against the spring means and against the shoulder.Finally, the closure is secured against the shoulder.

This invention is further directed to a manifold having an axial passagetherein and an opening in the manifold which intersects a cross-passageand extends to the axial passage. The manifold comprises a safety valvewhich comprises a closure at the outer end of the opening, a valve seatbetween said axial passage and the intersection of said opening and thecross-passage, a valve member slidable toward and away from the valveseat, and a spring means biasing the valve member against the valveseat.

Other objects and features will be in part apparent and in part pointedout hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of a manifold fitting of this invention;

FIG. 2 is a transverse section on line 2--2 of FIG. 1;

FIG. 3 is a transverse section on line 3--3 of FIG. 1;

FIG. 4 is an enlarged vertical section on line 4--4 of FIG. 1 showing afiller valve; and

FIG. 5 is a view illustrating a second embodiment of the invention.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, a manifold fitting of this invention,generally designated 1, is shown to comprise an elongate main body 3 ofhexagonal cross-section, its six faces being designated 3a, 3b, 3c, 3d,3e and 3f, and its ends being designated 4a and 4b. The body has alongitudinal passage 5 extending partway therethrough from end 4a towardend 4b, being of generally circular cross-section as shown in FIG. 2.Body 3 has an externally threaded first end portion 7 at the end 4b ofthe passage for attachment of the fitting 1 to a tank (not shown) forcommunication with the tank.

The main body 3 further has threaded lateral openings 19, 21 and 25therein, and one unthreaded opening 26 therein. The first lateralopening 19, which is an outlet opening, is in face 3e of the main bodyand has a threaded inner portion 19a and an unthreaded outer endcounterbore 19b of slightly larger diameter than the inner portion 19a.The second lateral opening 21 is in face 3b opposite face 3e and inaxial alignment with the outlet opening 19. The second opening 21 has athreaded outer portion 21a and an unthreaded inner end counterbore 21bof greater diameter than the outer portion 21a but of smaller diameterthan portion 19a of opening 19. The third lateral opening 25 is in face3d of the main body, of uniform diameter and threaded. The fourthlateral opening 26 is in face 3a and has an unthreaded inner end portion26a, an unthreaded outer end counterbore 26b of greater diameter thanthe inner portion 26a, and an unthreaded intermediate portion 26c ofdiameter greater than the inner portion 26a and smaller than the outerend counterbore 26b. Face 3a is crimped about opening 26 so as to lessenthe diameter of outer end counterbore 26b where it meets face 3a. Thelocation of the openings along the body 3 is not crucial to theoperation of this invention except that the outlet opening 19 and thesecond lateral opening 21 must be in axial alignment with each other.

An outlet member 27 illustrated as being a nipple comprising a tubularbody with a passage 29 therethrough, outer and inner threaded portions31 and 33 and a hexagonal head 35 therebetween is adapted to be threadedin the first lateral opening 19 with the inner portion 33 incommunication with passage 5. The diameter of the outer portion 31 ofthe outlet nipple 27 is greater than that of the inner end portion 33,and the outer portion 31 is adapted to threadably receive an air linefor the flow of compressed air from the tank, through passages 5 and 29,and into the line. An O-ring seal 37 is provided on the inner portion ofthe nipple 27 adjacent its hexagonal head 35 to seal the outlet opening19 at the junction of its inner and outer portions 19a and 19b when theoutlet nipple 27 is threaded therein. The hexagonal head 35 is adaptedto receive a suitable tool for tightening the outlet nipple in theopening 19.

The outlet nipple 27 has a valve seat 39 at its inner end. A valvemember 41 cooperable with the seat 39 is threadably fitted in the secondlateral opening 21. It comprises a cylindrical stem with first andsecond rings 43 and 45 at the inner end thereof, third and fourth rings47 and 49 intermediate its ends and a threaded outer end portion 51. AnO-ring seal 53 disposed between the first and second rings 43 and 45 isadapted to engage the valve seat at the inner end of the outlet nipple27 to block the passage of air through the outlet nipple, ring 43 beingof smaller diameter than ring 45. A second O-ring seal 55 between thethird and fourt rings 47 and 49 provides a slidable seal in the innerportion 21b of the second opening 21. The valve member 41 is threadedfrom the inside to the outside in the second lateral opening 21 andextends across the passage 5 with space therearound for the flow of air(see FIG. 3). The valve member 41 is adapted to be threaded inwardly inthe second lateral opening 21 for engagement of the O-ring seal 53 withthe valve seat 39 and outwardly with respect to the second lateralopening 21 to an open position for the flow of air from the tank throughthe passage 5 and through the outlet nipple passage 29. A knob 54 isattached to unthreaded portion 55 of the end of outer end portion 51 ofvalve member 41 for turning the member for inward and outward movement.

Valve member 41 further comprises a stem passage 56 extending inwardlypartway therethrough along its major axis from its outer end. Vents 56a,in valve member 41 allow air passage between stem passage 56 and axialpassage 5 of main body 3. Filler check valve 57 is threaded in passage56 for filling the tank with compressed air via application of acoupling at the end of a compressed air supply line (not shown). Thecheck valve 57, as shown in FIG. 5, is of the conventional well-knowntype used for inflating tires, having a tubular body 58, a stem 59therethrough and a spring (not shown) therein. The stem 59 has a valvemember 60 for blocking the inner end of the body 58 and is held againstthe opening by the spring. Air is permitted to pass through the body andpassage 56 of the valve member 41 by pressing inwardly on the outerportion 59a of the stem, thereby moving the valve member 60 away fromthe inner opening of the body and unblocking the passage through thecheck valve's body 58.

A pressure relief safety valve 61 is incorporated within the lateralopening 26 in the main body 3. Opening 26 has an unthreaded inner endportion 26a, an unthreaded outer end counterbore 26b of slightly greaterdiameter than the inner portion 26a, and an unthreaded intermediateportion 26c of diameter greater than the inner portion 26a and smallerthan the outer end counterbore 26b. Outwardly facing shoulder 26d isthereby formed between counterbore 26b and intermediate portion 26c.Inner portion 26a is formed to provide a valve seat 63 and having apassage 64 through said inner end portion (and seat) for flow of air tothe intermediate portion 26c of valve 61. A closure head 65 is situatedin the outer end counterbore 26b against shoulder 26d and held in placeby a portion of metal of face 3a swaged about the periphery of opening26 so as to lessen the diameter of outer end counterbore 26b where itmeets face 3a. The closure head has a central opening 67. A stem 69slidable in opening 67 has a valve member 71 at its inner end within thevalve 61 engageable with the seat 63. Spring means 73 interposed betweenthe valve member 71 and the closure 65 and biases the valve member 71 toits closed position engaging the seat. A cross passage through themanifold body 3 intersects opening 26 to form two lateral ports 77a, 77bextending through manifold body 3 in alignment with each other for theescape of air. Air is vented from the tank through ports 77a and 77bwhen the force of air on the valve head 71 exceeds the opening bias oron manually pulling the stem 69 by means of a ring 79 at the outer endof the stem 69.

The main body further has the threaded lateral opening 25 adapted toreceive a pressure gauge (not shown) for determining the pressure in thecompressed air tank.

A significant advantage of the manifold fitting of this invention is itsflexibility so far as the manufacturer is concerned for supplying it indifferent configurations to suit users' different requirements. Thus,for example, the manufacturer may supply the fitting with an outletmember at 27 having a female thread instead of the male thread at 31,the outlet member being threaded in the opening 19 and having a valveseat the same as at 39.

In view of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

What is claimed is:
 1. A manifold fitting for a compressed air tankcomprising:an elongate main body of hexagonal cross-section with firstand second ends, the first end being of reduced circular cross-section;said body having an axial passage extending from the first end towardand terminating short of the second end; said first end being externallythreaded for attachment of the fitting to a tank for communication withthe tank via the passage; said body having a first lateral openingextending inwardly to said axial passage from a first face of the sixfaces of the body; an outlet member threaded in said first lateralopening in the body having a valve seat at its inner end toward saidpassage; said body having a second lateral opening extending inwardly tosaid passage from a second of the six faces of the body opposite saidfirst face, said second lateral opening being opposite said firstlateral opening and in axial alignment therewith; a valve memberthreaded in said second lateral opening extending across said passagewith space around said valve member for flow of air, said valve memberbeing adapted to be threaded inwardly in said second lateral opening toa closed position in engagement with the valve seat and to be threadedoutwardly with respect to said second lateral opening to an openposition for flow of air from the tank through said passage and outthrough said outlet member, said valve member having a stem with anaxial stem passage therein extending inwardly partway from its outer endto at least one port in the valve stem for communication with the axialpassage in the main body; a filler check valve in the axial stem passageof said valve member for filling the tank with compressed air viaapplication of a coupling at the end of a compressed air supply to saidstem; said body having a third lateral opening extending inwardly from athird of said six faces to said passage; a pressure relief safety valveat said third lateral opening in the body; and said body having a fourththreaded lateral opening extending inwardly from a fourth of said facesto said passage for receiving a pressure gauge.
 2. A manifold as setforth in claim 1 wherein said body has a cross passage intersecting saidthird lateral opening and wherein said safety valve comprises a closureat the outer end of said third lateral opening, a valve seat betweensaid axial passage and the intersection of said third lateral openingand said cross passage, a valve member movable toward and away from saidsafety valve seat, and spring means biasing said safety valve memberagainst the safety valve seat.
 3. A manifold as set forth in claim 2wherein the outer end of said third lateral opening is of enlargeddiameter so as to form an outwardly-facing shoulder in said opening, andwherein the closure is secured against the shoulder in the outer portionof said third lateral opening by a swaged-over portion of the body atthe outer end of said third lateral opening.
 4. A manifold as set forthin claim 3 wherein an intermediate portion of said third lateral openingis of enlarged diameter with respect to an inner portion of said thirdlateral opening and the outer end of said third lateral opening is offurther enlarged diameter so as to form said outwardly-facing shoulderbetween the intermediate portion and the outer portion.